A report has suggested that the NHS could claw back more than £500 million a year if it was better at charging foreign nationals for using its services.

The health service could raise the cash – the equivalent of 0.45% of its annual budget – by deterring so-called “health tourists”, recovering care charges from overseas visitors and charging temporary migrants for accessing NHS care, the report suggests.

Health tourists – such as women travelling to the UK in late pregnancy to give birth in an NHS hospital before returning home – cost the health service at least £70 million each year, the study on migrant access to NHS care in England found.

Experts have previously raised concerns about the escalating costs of health tourism particularly across maternity services, oncology, HIV services, infertility and in the treatment of renal failure.

But a recent European Commission report concluded that so-called benefits tourism was “neither widespread nor systematic”.

The latest independent report, conducted by Creative Research on behalf of the Department of Health (DH), also estimates that £388 million could be recovered from patients who should pay for care but are not always currently charged by the NHS.

A DH spokeswoman said that only around 16% of this money is currently recovered by health service officials.

The report states the health service has “some of the most generous rules in the world”. At present only hospitals are required to charge for services and even then, emergency care is provided for free.

It concludes that the total cost of visitors and temporary migrants accessing NHS services is between £1.9 billion and £2 billion – but this figure includes some money that is already recovered.

The figures have been released ahead of the second reading of the Government’s Immigration Bill, which aims to bring in measures to stop migrants abusing public services and make it easier to remove people who should not be here.

Key measures in the Bill will see temporary migrants, such as overseas students pay to access the NHS, while the appeals process against deportation is to be streamlined.

Ministers hope the levy on students or foreign workers who come to the UK for more than half a year will generate £200 million a year.

The surcharge, combined with better recovery of costs and a deterrent on health tourism could save the health service “well over half a billion ponds”, the DH spokeswoman said.

Health Secretary Jeremy Hunt said that the NHS is a “national health service – not an international one”.

Mr Hunt has pledged to identify a “more efficient system” of claiming back costs and has also appointed Sir Keith Pearson to advise on visitor and migrant cost recovery.

He has also said he will be “introducing a simpler registration process to help identify earlier those patients who should be charged”.

Mr Hunt said the report shows there is a “serious problem”, adding: “Having a universal health service free at the point of use rightly makes us the envy of the world, but we must make sure the system is fair to the hard-working British taxpayers who fund it,” he said.

“We have one of the most generous systems in the world when it comes to health care for foreign visitors, but it’s time for action to ensure the NHS is a national health service - not an international one.

“With the NHS already under pressure from an ageing population, it cannot be right that large amounts of taxpayers’ money is being lost through treating people who should be paying from foreign countries.

“We are confident our new measures will make the NHS fairer and more sustainable for the British families and taxpayers it was set up to serve.”

Dr Chaand Nagpaul, chair of the British Medical Association’s GP committee, said: “Anyone seeking to access NHS services should be eligible to do so and we must consider any proposals for improving the current system of reclaiming healthcare costs from European or other governments whose citizens are treated by our health system

“However, there is limited evidence to suggest that migrants or short term visitors are consuming large parts of the NHS budget. The government’s estimates are based on a number of assumptions that result in a figure significantly higher than previous estimates.

“We must also be careful about creating a climate where some people are deterred from seeking treatment when they need it. Not only would this present a risk to the health of that individual, it could also prevent the NHS from identifying individuals with contagious diseases and result in further costs to the NHS should a patient’s condition deteriorate to the extent they require more expensive emergency treatment later on.”